1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device using a delta arrangement of pixels and a method of driving the same.
2. Description of the Related Art
The liquid crystal display device includes a pair of substrates, a liquid crystal layer held between the pair of substrates, and a display portion formed of a plurality of display pixels. In a case of a color type liquid crystal display device, each of the plurality of display pixels includes some kinds of color pixels.
Namely, when each of the display pixels is formed of a red pixel to display red color, a green pixel to display green color, and a blue pixel to display blue color, an arrangement method of pixels may be used, in which the red pixel, the blue pixel and the green pixel are arranged in a stripe shape so as to line every same color pixels.
When arranging the pixels in a stripe shape for every same color, the pixels that are arranged at the edge of the display portion are same color pixels in a direction where a stripe-like line extends. Therefore, a line of the single color might be recognized visually at the edge of the display portion. Furthermore, cracks between adjacent lines of the pixels arranged in a line may be also recognized visually in the stripe shape.
Other pixel arrangement (hereafter referred to a delta arrangement) which shifts each of adjacent pixels arranged in a row direction to 1.5 pixel span of each color pixel with respect to adjoining row lines of pixels is proposed in a Japanese laid open patent application No. 2000-194017. According to the delta arrangement, since the pixels of the same color are not arranged in a line at the end of a display portion, the line of a single color is not recognized visually at the end of the display portion. Furthermore, since the pixels are not lined in a column direction, the edge of the display portion is not recognized visually in a line shape, which prevents a decrease of the display quality.
Generally, the liquid crystal display device adopts an alternating electric field driving, that is, a polarity of a voltage applied to the liquid crystal layer is inversed in every selected scan line as countermeasure against flicker. However, if only one of the polarity changes in every selected scan line and every selected signal line is adopted, the flicker may be generated in a direction in which scan lines or signal lines extend. Accordingly, in a high quality liquid crystal display device, a dot inversion driving in which the polarity of the voltage applied to the liquid crystal layer is inversed both in every selected scan line and every selected signal line.
On the other hand, a capacitive coupling driving (CC driving) is proposed to decrease an amplitude of signal voltages. In the capacitive coupling driving, a predetermined pixel voltage is obtained by adding an auxiliary capacitance signal to a pixel electrode through an auxiliary capacitance. If the capacitance values of the auxiliary capacitance and a pixel capacitance are set substantially equal, the amplitude of the signal voltage is reduced by half.
On the other hand, a black insertion driving is known to prevent a smudgy display, that is, a scan for the black insertion driving and a scan for writing image signals into the pixel are conducted within one frame scan period. Furthermore, a selection driving is used to lower cost by reducing number of driver circuits and peripheral wiring area to achieve a narrow frame display.
In the case of the delta pixel arrangement is used, above described CC driving, the capacitive coupling dot inversion driving (CCDI driving), the selection driving, and the black insertion driving may be also applied to achieve the low power consumption and the narrow frame display. Here, especially, the CC driving applicable to the dot inversion driving is called a CCDI driving.
However, if the delta arrangement described in the laid open patent application is adopted, a pattern of the signal wiring for supplying picture signals to the plurality pixels in the liquid crystal display device becomes complicated, which results in difficulty of achieving the low power consumption and the narrow frame display by using the delta arrangement.
The present invention is accomplished in light of the above-mentioned circumstances. The purposes of the present invention is to provide a high quality liquid crystal display device and a method driving the same, using a delta arrangement capable of achieving a low power consumption and a narrow frame display device.